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DR. J. MURIE ON THE ANATOMY OF THE SEA-LION. 
longitudinal muscular layers, here assume oblique or transverse directions; and as 
“the muscles of the posterior limb in the Seal,” as Haughton’ has remarked, “ differ 
from those of other Carnivores principally in the shifting of their insertion to lower 
points of the leg,” so likewise in the Sea-lion this distal transference of insertion 
materially masks the usual relation of parts. 
Of the hind limb the free part, taken in a straight line, measures one foot and a half, 
the girth at the proximal end of this being 11 inches. When extended to the fullest, 
the greatest breadth of the foot is 10 inches; and as the phalanges are freely flexible 
laterally, and can override each other (vide Pl. LXVII. fig. 3), corresponding reduction 
of breadth consequently ensues according to the amount of overlap. 
The free part of the posterior extremity comprises little more than the foot and the 
turn of the ankle, the remainder of the limb being, so to speak, bound up with the 
pelvic region of the body, and moving synchronous with it; the very peculiar hobbling 
gait of the rump and its members is caused thereby. The hind differs very sensibly 
from the fore foot in figure; for whilst the hallux is absolutely large and long, it still 
is relatively shorter, narrower, and less developed than the pollex. The great toe has 
certainly the advantage of length; the others are subequal, or with slight diminution 
from the second to the fifth; and this applies to the phalangeal interspaces, or rather 
vacuities, betwixt the dermally covered, spatulate, terminal cartilages. 
Besides shape, the hind foot is very distinct from the fore one in the separate, raised 
character of the phalanges dorsally, these being firmly encased and comparatively 
undefined in the manus. ‘The pes is thus a far more moveable instrument, so far as 
its component parts are concerned; and though the leg is limited in action by being 
fastened as low as the heel, yet the hind flipper and its claws subserve all the ordinary 
purposes of the carnivore’s paw in scratching the body &c. In two of the figures 
(woodcuts, nos. 3 & 4) the attitudes assumed, and manner of use just spoken of, are 
shown as sketched from the living animal. 
On its upper surface the hind flipper is covered with short, here and there rough, 
adpressed hairs, which run down the back of each digit to within 15 inch of the nails; 
but the interspaces or intervening web, and the whole of the free edges of the digits, 
are more or less bare for 24 inches above the point mentioned. The skin of the dorsum 
is longitudinally wrinkled, and in certain positions has a tendency to become diamond- 
outlined. Of the five nails or claws, the three middle ones are large (13 inch long by 
33; inch broad) as compared with those on the hallux and little toe, which are mere 
rudimentary structures. The whole of the nails are situate not terminally, but at the 
proximal ends of the digital cartilages, and almost in a line transverse to each other. 
The sole, like the broad flat palm, is devoid of hair from the heel forwards, and, like 
it also, is covered with hard, callous, black epiderm. This likewise is thrown into fine 
2 Proc. Roy. Irish Acad. May 1864; but consult also Duvernoy, “ Sur les organes du mouvement du Phoque 
commun,” Mém, du Mus. d’Hist. Nat. vol. ix. 
